The present invention relates to a machine for filling containers, in particular bottles or the like, with a product particularly a liquid such as a drink, by means of a weighing system.
There are various types of machine for filling containers, in particular bottles or the like with a liquid. These machines include a transport system, which may be circular (distribution carousel or wheel) or linear (conveyor belt), on which the bottle is made to transit. Above the neck of the bottle a filling valve is placed which delivers the filling liquid taken from a special tank.
To prevent overfilling of the bottle, systems are designed which automatically detect the level of liquid in said bottle and interrupt the flow of liquid dispensed. Typically, the interruption signal is sent to a driving and control unit which then closes the filling valve.
These automatic detection systems are of various kinds. For example, some of them provide for reading the filling level using photoelectric cells or suitable viewing systems (i.e. cameras). Others provide for the introduction of a suitable sensor through the neck of the bottle to detect the filling level and send the interruption signal to the driving and control unit.
One system that has proved effective and of limited cost, provides for weighing the container and interrupting filling at a predetermined weight. This system also has limited overall dimensions, since it can be integrated into the bottle support members.
If the bottle is in a heavy material such as glass, it can easily be supported by a special plate placed along the periphery of a carousel or a wheel transport system. Below the plate a weighing system is positioned which detects the weight of the bottle and, when reaching the predetermined weight, sends an interruption signal to the driving and control unit of the machine, which in turn cuts off the flow of liquid by closing the filling valve.
This system must be calibrated according to the container to be filled and the filling liquid, but is in itself efficient and profitable.
When the bottle is in a lightweight material such as plastic, the plate support system can no longer be used because the bottle would not have the necessary stability. In these cases therefore the bottle is moved keeping it suspended by the neck using suitable clamps which are positioned at the collar ring. This means that regardless of the size of the bottle, the neck with the collar ring always has the same shape, a feature that allows a substantial mechanical simplification of the machine.